Spirit level



H. STAHLIN May 2, 1 950 I SPIRIT LEVEL I 2 Sheets-Sheet l Filed Feb. 6, 1945 Gttorneg M y 1950 I H. STAHLIN 2,506,115

SPIRIT LEVEL Filed Feb. 6, 1945 2 Sheets-Sheet? Z f2 g. 7]

flaw/d aim/i? I attorney Patented May 2, 1 950 UNITED STATES PATENT OFFICE SPIRIT LEVEL Harold Stahlin, Portland, Oreg.

Application February 6, 1945, Serial No. 576,392

2 Claims.

My present invention relates to an improved spirit level of the type employing a rotatable and automatically adjustable bubble tube mounted in a straight edge for co-action with a circular stationary calibrated index or three-hundred and sixty degree scale of the instrument. By the utilization of the combined straight edge or rule and the rotatable-bubble tube and its duplicate pointers, the instrument is readily adapted for use by carpenters, brick layers and masons, plumbers,and others, in measuring angles, slopes, and inclines from a horizontal plane; for fixing either a vertical line or a horizontal standard line of direction, and for plumbing operations for various other purposes.

In the accompanying drawings two forms of the invention are illustrated, one-of which involves an illuminating feature, and both of which include combinations and arrangements of a cylindrical casing, a manually rotatable carrier mounted in the casing and a bubble tube mounted in the carrier, together with co-acting means of the casing and carrier for guiding the carrier vention.

Figure 1 is a perspective view of a'geometrical instrument embodying my invention, showing, in addition to the rotatable spirit level, ahorizontal level and a vertical level, to facilitate the use of the instrument.

Figure 2 is an enlarged face view of a portion of the stock of the level, and disclosing the rotatable or oscillatable bubblev tube of the spirit level.

Figure 3 is a transverse sectional view at line 3-3 of Fig. 2 showing the interior arrangement of the instrument.

Figure 4 is a sectional stock, as at line 4--4 of Fig. 2, showing the bubble tube in full and the exterior knobs for manually adjusting the tube and its pointers.

Figure 5 is a fragmentary detail view showing the inside of the fixed cylindrical casing, and its scale ring, or guide for the pointers of the rotatable or oscillatable bubble tube.

Figure 6 is a detail view, partly in section, of the detached bubble tube.

Figure '7 is an enlarged detail sectional view at one end of the bubble tube showing one of view of the level and the tube-heads and its guide-pointer, or indica I tor.

and structure type, wherein the stock is broken away to disclose an electric light for illuminating the calibrated scale of the level.

Figure 9 is a transverse sectional view at line 99 of Figure 8 showing the interior of the spirit.

level with its reflex illuminating surfaces.

Figure 10 is a detail view, partly in section, of

the fixed casing of Figure 8 showing its light reflecting surfaces.

Figure 11 is a longitudinal sectional View of a portion of the stock of the instrument, showing,

the fixed casing, and the adjustable tube in section.

a stock or straight edge S, which may be fashioned of wood, molded plastic material, or of any other suitable material, and provided with opening of the stock S which opening is fashioned with annular beveled edges B at the opposite sides of the stock, and an enclosing casing is fixed within the transverse opening for supporting the spirit level. The fixed casing includes an inner cylindrical band I, having an interior burnished light reflecting surface, and provided with external screw threads. The light reflecting sur-:

face is fashioned with an annular flange or guide ring 2, both sides of which are graduated or calibrated with scales including three hundred and sixty degrees in angular marks. The externally threaded cylindrical band is provided with a pair of exterior sleeves 3 and 4 threaded on the band from opposite sides, and two transparent circular disks 5, 5, of suitable material provide windows at the opposite sides of the stock.

The round windows 5, 5, are retained in position by means of bevel edges or flanges 6, 6, of the sleeves 3 and 4 that hold the bevel edges of the windows against the outer opposite edges of the iimer band I; and the structure thus described provides an enclosure and support for the transparent bubble tube 1, which may be of glass or other suitable material.

The open ends of the cylindrical bubble tube are closed by means of two plugs 8, 8, each fashioned with an exterior bifurcated nib 9 having Figure 8 is a face view of a portion of a modifled form of the spirit level, of the combined light The spirit level of the invention is embodied in a guide slot l0, and the usual fluent material, as alcohol, with its indicating bubble, is contained in the closed tube. The bifurcated nibs, as indicated, straddle the annular flange or guide ring 2 of the casing, and the coacting nibs and ring, in addition to guiding and retaining the bubble tube in proper position, the nibs form pointers or indicators for use with the calibrated scales on the opposite facesrofflthe guide ring.

The bubble tube=is rigidly mounted-Iin'a carrieror holder which includes a yoke having parallel arms II, II, and spaced bushings i2, t2, the latter,

surrounding the opposite ends of the tube; and the carrier is provided with alined trunnions B513 mounted in bearing bushings or rings H5, 14 fixed in central openings of the oppositelyarranged windows '5, 5. By means of a-,-.p air of. exteriors.

knurled knobs l5, l5, rigid with the trunnions, the bubble tube assembly may manually be tilrned as desired, as for instance in measuring angles fromaastandardline:

In the form of the invention illustrated in;

Figures 81-l,- a=spi ritrlevel ofxthezcombinedz-light andlstructure -typ'e-isdepicted, whichiorm of in.-

stl ument with' its-illuminating.features, is .espe-.

fashioned with.spaced, exterior. annular guide flanges 22, 1 22,- extending along the sidesioftheu circumferential light slo.ts,-.is.mounted in a casing; fixed: in an suitable. socket. or; transverse; opening; throughithe stock S..of; the. instrument. This;

generally" cylindrical,-. fixed: casing; has a; centralannular; exterior. projection: 23 forming, anainte rior channel having interior reflecting faces or: surfaces;.andrthe channelreceives and retainsthe guidetflanges 22, 2-2:, of the rotatableor oscillatable1 carrier:

Atlthe opposite sides .of; theaannular proj ection, 23uare;integral annularcwalls 24,.24-,.each oi'which. terminates in;arr.-annular; beyelednflangelzfi, 25, andzthe: exposed;.faces:; on these. flanges are: callbratediatcZ 6'; .2'6,.througlr; three hundred and sixty;

degrees; forsjoint us'e with the-nib onpointer; 25!;

onithe, bubble tube: I 6..

The fixedcasing, withlitsiexterior. annular pro. jection; or; rib 23, is rigidly mounted in a. socket;

of the'stock S; andthesocketforms theterminal.

portion of an interior longitudinally disposed lightchamber' 28,-. and the. walls of thecasing,

adjoining the lightchamber are. cut away, as-.at=-

29;.2.9,,as-best seen inFig. 11, to permit uninterrupted lightv rays from an. electric lamp 39 to; enter-"the interior of the casing, and-to illuminate the calibrations 26, 26.

The bubble :tubea 95,- with. its. bubble A conventional type of portable electric lamp, or flashlight, is illustrated as mounted within a recess in the interior of the stock, and the lamp is controlled in usual manner by a switch located in position where it is readily accessible.

In addition to the specific light reflecting surface of the channel 23 of the casing, various other interior surfaces and parts of the casing, and also of the adjustable carrier and bubble tube, may be fashionediof imaterialatliat-is transparent, and which takes a highpolish, toaidinth'e transmission of light and illumination of the two three hundred and sixty degree scales.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1...In;alspirit.w1evel, the combination with a stock and a casing fixed therein, said casing including'andnner cylindrical band having an inner annular calibrated flange, an opposed threaded pairsofzexterior sleereszmountedronethezbemd, and a :pairt otspacerhztranspanentmindnms zclosing they ends: of the; band andrsecurediz thereto;- byc'saidzi sleeves;::oira:-manually rotatable carrientnunnions journallediinzsaid-windowszand fixedztoisaidrcarerier; asbubble:tubeamountediimthe: carrier; andsbifurcated: nibs iatithfii endsiofithe: tube; coracting with;the'.flange;zf.or :thezpnrposeszdescribed;

2, Iina...spiritlevelztheicombination with a stocks:

of; a; cylindrical 1:. band haying, anrinterior: lightlv -ent circular disks closingl ithegendsmf,the-eband the sleeves haying-flanges clamping the-said-disks against theends-oithe ;-band,. a:bubble;-tube ha -ing bifurcated nibs at .-its.-opposite .endsstraddlingthe. annular fiange-,..a.-carrier. yoke; haying.spacedv arms, bushings-.connectingthe endsuof. saidarms 1 and surrounding jthe bubble. tube, aligned ,trum, I

nions, on .said. arms extending.,-outwar.dly through. said. windows -andiiournalled. .therein,,and. knobsf. on. said trunnionsl outwardly ofthe. windows,

whereby thebubble tube ispoperable andfthezcali brations are .readablefrom both sides of .the level" stock.-

HAROLD STAHLIN.

REF EEENGE S The following references are ofrecord miller file of. this, patent UNI'IIIEIZL STAIESwBAiIENfIJSi 

